A long standing problem in the area of containers and conduits containing, in particular, hot water is that if a leak or break were to occur in the tank or conduit, no practical means or method exist for terminating the water input to the tank or conduit unless one is physically present at the time that the leak initiates.
The consequences of this problem is well known to the home owner, or tenant, who has experienced a burst hot water tank or a broken water supply through an apparatus making use of a hot water tank.
In the prior art, certain rudimentary efforts have been made to afford an automatic water cut off. Such prior art is reflected in U.S. Pat. No. 3,473,553 (1969) to Collins, entitled Water Cut Off Water Heaters; U.S. Pat. No. 3,920,031 (1975) to Maxfield, entitled Safety Shut Off Device; and U.S. Pat. No. 4,805,662 (1989) to Moody, entitled Hot Water Heater Failure Protection Device with Solenoid.
The structure of Collins is a purely mechanical device and, as such, does not make use of state of the art electromechanical components which are now available. Further, the device of Collins will not sense a leak which occurs at the lateral sides or top of a hot water tank.
The structure of Maxfield as in the case of Moody, operates only to sense accumulation of moisture or liquid below the tank, that is, in the so-called drip pan. Further, the solenoid thereof operates in a mechanical fashion which increases the possibility of failure over the extended time period that any vessel overflow control system must function.
The above reference to Moody makes use of a ground fault interpreter circuit which, for its operation, requires that the hot water heater failure system be continuously powered by a 120 volt alternating current. Accordingly, the system of Moody, while solving one problem, substitutes therefore a serious safety hazard which also has connected with it a considerable cost in power.
The instant invention addresses the long-felt problem of liquid vessel overflow control while overcoming the above set forth shortcomings of safety and cost in the prior art.